Videohash

- Windows OS support added.

- Make the collage as close to a square close as possible. This change decreased the hashdiff of partially similar files by 15.33%(mean), tested on 164 partially similar NASA public domain files.

- added useful exceptions
- avoid Redefining built-in 'hash'

- Users can now choosing other hashing algorithms using `image_hash="name_of_algo"`

updating readme and fix typo. Code is same as v1.0.0

first public release